Join the Hacktoberfest Open-Source AI Challenge: Touch Grass! $2,450 in Prizes Across 17 Winners.

Week 1 of our five Hacktoberfest DEV Challenges starts today! Running through October 11, the...

Week 1 of our five Hacktoberfest DEV Challenges starts today! Running through October 11, the Hacktoberfest Open-Source AI Challenge: Week 1 gives you a full week to build.

**This year's Hacktoberfest is all about building brand-new projects with open-source AI and open-weight models. Here's everything you need to know about Hacktoberfest 2026.

Missed the Hacktoberfest Weekend Challenge? No problem. Every challenge is a fresh start, so you're competing on the same footing as everyone else.

This week, we'll select one overall winner and a winner in each of our 16 partner categories. See all five challenges and every partner category on the HF26 DEV Challenge Hub.

Let's get to it!

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This week's theme: Touch Grass

Build something with open-weight models or open-source AI that gets people off the screen and into the world.

That can mean running an open-weight model, building on an open-source agent harness or framework, running inference locally, or all three. Whatever you pick, the open pieces should be what makes your project work.

Hiking, gardening, birding, run clubs, fall foliage: if it gets someone outside, it counts. The best builds here should make the screen the shortest part of the experience. A few ideas to get you going:

• A bird call identifier that works on the trail with no signal
• A garden planner that tells you what to plant this week based on your local frost dates
• A run club route builder that finds the best fall foliage near you

In your post, tell us why open innovation matters for what you built. Does it run on a phone in the backcountry with no internet? Keep someone's location data off a server they don't control? Let you fine-tune, swap models, or change how your agent behaves? Cost nothing to run? Tell us where your open-based approach worked better than a closed one.

Bonus points if you take it outside, use it, and tell us how it went.

{% cta https://dev.to/new?prefill=---%0Atitle%3A%20%0Apublished%3A%20%0Atags%3A%20devchallenge%2C%20hf26challenge%0A---%0A%0A%2AThis%20is%20a%20submission%20for%20the%20%5BHacktoberfest%20Open-Source%20AI%20Challenge%20Week%201%3A%20Touch%20Grass%5D%28https%3A%2F%2Fdev.to%2Fchallenges%2Fhacktoberfest-week1-2026-10-05%29%2A%0A%0A%23%23%20What%20I%20Built%0A%3C%21--%20What%20does%20it%20do%2C%20and%20how%20does%20it%20get%20people%20off%20the%20screen%20and%20into%20the%20world%3F%20%20Who%20is%20it%20for%3F%20--%3E%0A%0A%23%23%20Demo%0A%3C%21--%20Share%20a%20deployed%20link%20or%20a%20video%20demo.%20--%3E%0A%0A%23%23%20Code%0A%3C%21--%20Show%20us%20the%20code%21%20%20You%20can%20embed%20a%20GitHub%20repo%20directly%20into%20your%20post.%20--%3E%0A%0A%23%23%20How%20I%20Built%20It%0A%3C%21--%20Which%20open-source%20AI%20did%20you%20use%20%28open-weight%20models%2C%20agent%20harnesses%2C%20frameworks%2C%20local%20inference%29%2C%20and%20how%20is%20your%20project%20built%20around%20it%3F%20--%3E%0A%0A%23%23%20Why%20Does%20Open%20Innovation%20Matter%3F%0A%3C%21--%20Why%20does%20open%20innovation%20matter%20for%20what%20you%20built%3F%20%20What%20did%20it%20make%20possible%20that%20a%20closed%20API%20wouldn%27t%3F%20--%3E%0A%0A%23%23%20My%20Agent%20Session%0A%3C%21--%20Optional%2C%20but%20judges%20love%20it.%20%20Save%20your%20session%20with%20DevRelay%20and%20embed%20it%20with%20the%20agent_session%20tag%20%28see%20the%20challenge%20page%29%2C%20or%20link%20to%20it.%20--%3E%0A%0A%23%23%20Prize%20Categories%0A%3C%21--%20Which%20partner%20categories%20are%20you%20entering%3F%20%20List%20every%20one%20that%20applies%2C%20or%20remove%20this%20section.%20--%3E%0A%0A%3C%21--%20Team%20Submissions%3A%20Please%20pick%20one%20member%20to%20publish%20the%20submission%20and%20credit%20teammates%20by%20listing%20their%20DEV%20usernames%20directly%20in%20the%20body%20of%20the%20post.%20--%3E%0A%0A%3C%21--%20Thanks%20for%20participating%21%20--%3E%0A %} Touch Grass Submission Template {% endcta %}

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Prize Categories

Alongside our overall winner, we have 16 prize categories for projects that use a specific partner's technology. You don't need to use any of these to win the overall prize, but if you've been curious about any of this tech, this is a great excuse to give one a try. Full descriptions are on the hub.

Featured categories:

• Best Use of Render
• Best Use of TabPFN
• Best Use of Tinker
• Best Use of Arduino
• Best Use of DigitalOcean
• Best Use of Gemma

Partner categories:

• Best Use of Backboard
• Best Use of ElevenLabs
• Best Use of Entire
• Best Use of GitHub Copilot
• Best Use of Mastra
• Best Use of MongoDB Atlas
• Best Use of Sentry Agent Tracing
• Best Use of SerpApi
• Best Use of Temporal
• Best Use of Tiger Data

Pro Tip: Partner category winners come from a smaller pool of submissions, so your odds are meaningfully higher.

Note: One project can enter every category it genuinely uses, but you can only win once per challenge, and we'll aim to celebrate as many different builders as possible across the month.

Free credits: several partners are giving participants credits and promo codes, including Tinker, Render, Backboard, and ElevenLabs. Claim yours at hacktoberfest.com/my.

A huge thank you to our partners for making these prizes possible!

Judging Criteria

This is DEV, so your write-up matters most.

• Writing Quality (weighted most heavily): Is the post clear and engaging? Does it explain what you built, who it's for, and why open innovation matters?
• Relevance to the Prompt and Theme: Is open-source AI or open-weight models at the core of the project? Does it get people off the screen and into the world?
• Creativity: Is it an original idea, or a fresh take on a familiar problem?
• Technical Execution: Does it work, and is it well built?
• Use of Partner Technology (optional): If you're entering a partner category, does the project use that technology in a meaningful way?

Show your work. We'd love to see how you built it. Save your agent session with DevRelay and embed it in your post, or link to it. It's optional, but it helps the judges understand your process.

Prizes

• Overall winner (1): $250 USD, a DEV++ membership, and an exclusive DEV badge
• Featured category winners (6): $200 USD and an exclusive DEV badge each
• Partner category winners (10): $100 USD and an exclusive DEV badge each

All participants with a valid submission will receive a completion badge.

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How To Participate

Publish a post on DEV using the submission template below. Tell us what you built and how it gets people outside, show us a demo, and explain why open innovation matters for what you built.

{% cta https://dev.to/new?prefill=---%0Atitle%3A%20%0Apublished%3A%20%0Atags%3A%20devchallenge%2C%20hf26challenge%0A---%0A%0A%2AThis%20is%20a%20submission%20for%20the%20%5BHacktoberfest%20Open-Source%20AI%20Challenge%20Week%201%3A%20Touch%20Grass%5D%28https%3A%2F%2Fdev.to%2Fchallenges%2Fhacktoberfest-week1-2026-10-05%29%2A%0A%0A%23%23%20What%20I%20Built%0A%3C%21--%20What%20does%20it%20do%2C%20and%20how%20does%20it%20get%20people%20off%20the%20screen%20and%20into%20the%20world%3F%20%20Who%20is%20it%20for%3F%20--%3E%0A%0A%23%23%20Demo%0A%3C%21--%20Share%20a%20deployed%20link%20or%20a%20video%20demo.%20--%3E%0A%0A%23%23%20Code%0A%3C%21--%20Show%20us%20the%20code%21%20%20You%20can%20embed%20a%20GitHub%20repo%20directly%20into%20your%20post.%20--%3E%0A%0A%23%23%20How%20I%20Built%20It%0A%3C%21--%20Which%20open-source%20AI%20did%20you%20use%20%28open-weight%20models%2C%20agent%20harnesses%2C%20frameworks%2C%20local%20inference%29%2C%20and%20how%20is%20your%20project%20built%20around%20it%3F%20--%3E%0A%0A%23%23%20Why%20Does%20Open%20Innovation%20Matter%3F%0A%3C%21--%20Why%20does%20open%20innovation%20matter%20for%20what%20you%20built%3F%20%20What%20did%20it%20make%20possible%20that%20a%20closed%20API%20wouldn%27t%3F%20--%3E%0A%0A%23%23%20My%20Agent%20Session%0A%3C%21--%20Optional%2C%20but%20judges%20love%20it.%20%20Save%20your%20session%20with%20DevRelay%20and%20embed%20it%20with%20the%20agent_session%20tag%20%28see%20the%20challenge%20page%29%2C%20or%20link%20to%20it.%20--%3E%0A%0A%23%23%20Prize%20Categories%0A%3C%21--%20Which%20partner%20categories%20are%20you%20entering%3F%20%20List%20every%20one%20that%20applies%2C%20or%20remove%20this%20section.%20--%3E%0A%0A%3C%21--%20Team%20Submissions%3A%20Please%20pick%20one%20member%20to%20publish%20the%20submission%20and%20credit%20teammates%20by%20listing%20their%20DEV%20usernames%20directly%20in%20the%20body%20of%20the%20post.%20--%3E%0A%0A%3C%21--%20Thanks%20for%20participating%21%20--%3E%0A %} Touch Grass Submission Template {% endcta %}

Please review our judging criteria, rules, guidelines, and FAQ page before submitting so you understand our participation guidelines and official contest rules, such as eligibility requirements.

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Need Help?

• New to Hacktoberfest this year? Start with Everything You Need To Know About Hacktoberfest 2026.
• Come hang out and ask questions in the MLH Discord.
• The challenge page has resources from our partners to help you get started.

Important Dates

• October 5: Hacktoberfest Open-Source AI Challenge: Week 1 begins!
• <mark>October 11: Submissions due at 11:59 PM PDT</mark>
• Week of October 12: Winners announced

Week 2 launches Monday, October 12 with a brand-new theme. Follow #hf26challenge so you don't miss the reveal.

Questions about the challenge? Drop them in the comments below.

Happy Hacktoberfest, and good luck!